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package examples.concurrency.javatutorial.producerconsumer;

// The Drop class was written in order to demonstrate guarded blocks.
// Try using an existing data structure in the Java Collections Framework
// before trying to code your own data-sharing object.

public class Drop {
    // Message sent from producer to consumer.
    private String message;
    // True if consumer should wait for producer to send message,
    // false if producer should wait for consumer to retrieve message.
    private boolean empty = true;

    public synchronized String take() {
        // Wait until message is available.
        while (empty) {
            try {
                wait();
            } catch (InterruptedException e) {
            }
        }
        // Toggle status.
        empty = true;
        // Notify producer that status has changed.
        notifyAll();
        return message;
    }

    public synchronized void put(String message) {
        // Wait until message has been retrieved.
        while (!empty) {
            try {
                wait();
            } catch (InterruptedException e) {
            }
        }
        // Toggle status.
        empty = false;
        // Store message.
        this.message = message;
        // Notify consumer that status has changed.
        notifyAll();
    }
}
